In accordance with different positions of high speed train in tunnel,unsteady flow formulas for the evaluation of piston wind velocities in tunnel and aerodynamic drag on trains have been established in this paper.

• 针对高速列车在隧道中不同位置处行驶时，本文分三种情形建立了非恒定流活塞风计算公式，并建立了适用于非恒定流的类似于原朝茂公式的空气阻力计算方法。